There have been no documented cases of disease from bedbugs, but health officials say the bites can cause painful skin irritations, as well as anxiety and embarrassment. Cases have been identified in Lexington in "residential and dormitory settings," officials said in a statement, although they declined to identify the locations.

Late yesterday afternoon, however, the University of Kentucky confirmed that one case of bedbugs was identified in a single room at a UK residence hall in September. UK did not identify the dorm, but said the room involved has been closed and will remained sealed until pesticide treatments are completed. Transylvania University has not had a case, officials there said.

Bedbugs long carried a stigma of occurring only in unclean housing. But UK entomologist Michael Potter, a nationally recognized expert on bedbugs, says that's a myth and that he's heard of the parasitic insects turning up in all kinds of places, from vehicle upholstery to high-end family homes.

"They don't discriminate about socio-economic status," he said.

Bedbugs were common in the U.S. until about 1940, but DDT and other pesticides eradicated them in most areas after World War II. Now, Potter says, the bugs are on the march again in many parts of the country. It isn't clear why that's happening, but Potter said bedbugs could become the biggest entomological problem of the 21st century if the trend continues.